Tunnel-kiln with sectional combustion-chambers



DH. DRESSLER. TUNNEL KlLN WITH sEcioNAL COMBUSTIONGHAMBERS.

` APPLICATION FILED MAR. I27, 1920, 1,384,435.

Patented July 12, 19.21.

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F. DH. DRESSLER.

TUNNEL KILN WITH sEcTloNAL coMBusTmN CHAMBERS.

APP'LICATION FILED MAR.27|1920.

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Unirse s'rsrss PATENT orFlcE.

:mirar Dirt. nsnssnnn, or zANEsvILLE. offro.' .assIGNoR To AMERICAN DREssLER;

Tommi. mins, rive., or New YORK, N. Y., A soRroRATIoN or New Yom;

TUNNEL-KI'LN W'l SECTIONAL COMBSTN-CHAMBERS.

instales..

Specification of Letters Patent. Ptnfd July 12, 1921,

Application filed March 27, 19520. Serial No. 369,414.-

To all lu hom 'it m (1.1/ #officers Be it known that l". lHrLir nl-l. Dnnssnnn, a subject ot' the Kinoof Great Britain, and a resident ot' Zanesville, in the county of Muskingum and State or Ohio, have invented certain new and useful lmpriiveinents in Tunnel-lililns with Sectional Combustion- Chambers, of which the following` is a Speci- I'ication.A

My present invention comprises improvements in continuous tunnel kilns heated by internal combustion chainliers, devised with the general object in, view of making possible the eli'ective cinnbustion ot a larger amount o l ons and a consequent greater greneration ot' heat in. the combustion chambers of such a kiln than is possible with the ordinary kiln arrangements heretofore employed and at the same time securing; a desirable control of the hcatiiron of the kiln in dit'- 'tercnt sections along` its length. Another object of the invention is to provide an improved arrangement 'tor utilizing the heat in the escapingr products ot combustion to preheat the air supplied to support combustion. My improved air prcheating' means while of an especial value in connection with the apparatus devised for carryingv out the mein object of my invention is not restricted to sur-.h use.

'l`ho various 'features ot' novelty which characterize my invention are pointed out with particularity in the claims annex-ed to and forming" a part ot' this specification;

For a better understanding ot the invention, however, and the advantages possessed by it and specific objects obtained with it, reference should he had to the accompanying dra Wings and descriptive matter in which l have illustrated and described e preferred embodiment of the invention.

the drawingsr t mgure l 1s a diagrammatic plain with erts broken away and in section of one crm ot' kiln embodying my presentinvention;

Fig. 2 is s view teken similarly to l of a portion of e modified construction;

Fig. 3 is a sectional plan on a larger scale olf s portion oi the apparatus shown in Fig'. 2; and

Fig.' 1t is a section on the line Lit-l of Fi 3. il lig. l have illustrated the use of my invention 1n a tunnel klln compmsing e.

heating-up zone B', a hotY zone' :und a coolingr zone B3. The hot zone" B? o?? the kiln is heated by combustion 'chambers` C', C2 and C3 at the opposite sides of the path way for the goods carrying cars. The con@ bustion chambers shown, individually con sidered, are ot' the type and arrangement commonly employed in the well-known Dressler tunnel kiln, shown for example in the patent of Conrad Dressler No. 1,170,428, in that they are arranged on masonry benches or ledges at the 'side of the pathway of the goods carryingJ car (as shown in Fig. et) and are formed with open ended passages C* in their walls whereby the kiln atmosphere is caused to circulate upward through 'the passages CL past the combustion cha-mber proper, and down through or elongthe Zgoods between the combustionchambers at the opposite sides of the kiln. My present invention is distinguished from the ordinary type of Dressler kiln however, by the arrangement 0l' a plurality of relatively short 'combustion chambers C', C2 and C3 in an end to end series at each side of the kiln and extending the length of the hot zone B2 of the kiln; whereas in the ordintiryvarrangement there is e single combustion chamber at each side oi the kiln extending the ull length of the hot zone.

Each or' the various combustion chambers C', (l2 and C is preferably provided with one or more separate valved gas supply connections D, a separate air inlet -E and a separate outlet F for the products of combustion.' Advantageously, as shown, each air inlet E is providedwith an 'individual damper or regulating device E', and each outlet IF for products ofcombustion is similei-ly provided with an'individual regulable damper F. As shown, the air inlets E for the dille-rent combustion chambers stre su plied from the common pipe conduit 2 of combustion from the. combustion chumbers C', C2 and lC3 at each' side of the kiln 'are connected toa corresponding conduit F2 connected at F3 to a stack or exha-uster (not shoWn)-. A branch F* from each con-A duit F9, preferably controlled bythe regulating damper F5 forms a means for passing products of combustion from the conduit F2 to heat radiating pipes I located in the lheating-up zone B of the kiln: The ends lof the pipes I adjacent the corresponding end of the kiln are connected by a conduit I to a suitable stack or other device not .shovvnin the drawing for drawing products of combustion through the pipes I.

In the operation of the apparatus shown in Fig. l the goods to be heated enter the kiln through the ante chamber K and are carried by cars or other suitable transporting means from the ante chamber through the kiln proper in a continuous stream, leaving the kiln through the exit chamber L. The goods are heated up more or less gradually as'they pass vthrough the heating-up zone B and then kept at a high temperature which may or may not be constant, depending on conditions, in their iassage through the hot zone B2. In the su sequent passage of the goods through the cooling-off zone B3 the heat in the .goods and goods carrier is absorbed to a considerable extent by the pipes H3 and is utilized in preheating the air passmuni internal dimension of the combustion chamber transverseI to its length is'in the neighborhood of three' feet', IWill ordinarily make the combustion chambers arranged in accordance with the present invention', each of a length of from fifteen to thirty feet. Nith these proportions it is possible to substantially fill each combustion chamber with burning products of combustion throughout a'large portion of its length and to maintain a desirable rate of flow through the cham bei'. jvvhile maintaining a pressure in the chamber differing only by a few millimeters of Water from atmospheric pressure.

The replacement of the single long combustion chamber heretofore ordinarily pro'- vided at each side of the kiln and extending the full length of the hot zone, by a plurality of separate combustion chambers arranged in an end to end series makes it possible to supply more heat to anelcingated hot zone in a kiln of given cross section of kiln chamber and combustion chamber-than is practically possible vvhere each combustion chamber runs the full length of the hot Zone. The amount of gas or other fuel preciable difference between the pressure iii.

the combustion chamber and the pressure surrounding the combustion chamber. Vtith the present invention it is possible to main tain practically the maximum combustion chamber temperature throughout the length of an elongated hot zone, whereas With single elongated combustion chamber extending the full length of a longliot Zone, VAthe combustion chamber is, in practice', inevitthan at the end at which combustion begins.

The division of the combustionk cltiainbers" into sections not only makes it possible' to maintain -a substantial uniform combustion chamber temperature from one end of the 'ably substantially cooler at its outlet end hot Zone to the other notwithstanding fariations in the rate at which heat is absorbed in different portions of the hot zone but makes it possible to vary the combustion chamber temperature along the length ofx the hot zone as conditions may make desirable. Still another advantage of the sectional combustion chamber coiistruction'iethat it makes it possible to take care of the expansion and contraction resulting from cha? 'es in the temperature of the high temperati e portion of the kiln in a very, simpie and satisfactory manner. To take, care of thermal expansion and contraction it is ordinarily necessary to divide the walls of the lcombustion chamber structure Aproper into sections separated by transverse expansion in joints J. With kiln constructed inl accordance with the present invention, .i

place one ofthese expansion joints'betfveen each pair of "adjacent combustion chamber sections. ln. consequence, the relative movement between each such section of the kiln structure'propei, and the combustion chamber located in it,.lis appreciably less than is the case where a single combustion chamber extends lilniwisel through several sections of the kiln separated from one another by expansion joints.

`With the relatively large amounts of fuel which may be burned iii'the hot zone of a kiln constructed in accordance with the present invention, it will not ordinarily be practically possibleto eifectually utilize all the ailable heat in the Waste. products of j combustion leaving the combustion chambers in the heating-up zone of an ordinary kiln. If all the Waste products from the combustion chambers are passed through the heatu zione? the goed@ wiif haai, u, to@ melma ii pi'ofluu of drawn tiiimfgii time heating y i sur?, that ev Stili contain auch en l' i but.:

um im.' uiiizin.

`Clin prop@ cumbustimi chiami,

A L ad Y Y EA. mtr) an The lafzesz, m the Temperatur, the cc'ecitly spaced apa-rt, and

the Combi; on in @zich combustion chamber :may b@ independelibly eguiaeL ami desired amounts of air and gas m' y be humm? .in mail ccmbustion chamber With- @uit 0i the iiibusiuii chamber U1* r The mwpemims me not only simpie :mi eecmve, bui, am con] ed with '11 glv a compact rsrucifure which' is Qasy io 233)@ iai reciiqgie'siaoi' construction discloed imi; cimmed helfen) is cimmed 1n divisimmi appllcfgtlon, Serial Juil@ "i8, 192).

A claim new and to secure by Lathe kiln rtsi/rimini@ in such a, manner i0 ascaveiy insula@ agamsi heatiiosses. The

Having now fiesi'ibed my 'nvantiomwimi i 'tais .Pfliiig is:

i Mm-@n with a kiki Chamber having am mongaed hoi, mns, @if a. piurahty of @oliv vbustin Qimmbem al'xzmged in an and to @mi Series @Vending ionggimdina'ly of the hot :come and having am muil aras inlets ai; one

tion at the other end and of such pmpoi "Lions timt the isbance bewffn tha inlet and oude?, mi: @zich @aambeiis sevegi times xmimum iinsi'f'ise dinmnsimi of #ne chamijiQf, l

The mmhiimiion in tunne kiiixxwith vminer having; an elfongatec im?) aiidwo vT isbion chambers iiez'em zwi'awei iii im 'and to and, series, of aA coiffe f o ng series of recupez'atos :Lrmnge eoiribusfigm chamber and Connected to the Th@ f eoniiiinmion in a, tunnel kiki.L wiii kiln cimmber ami a, com''msatign cimmand ghe Vin ci ibm "alongside die com- ?misim jrimmhel- :nifl Connecte" at one ab@ the resupemor and it oppor-siii@ @mi t@ he ai combustion ffm 'mik o ciL, this "fd da 01E Wiardi,

N0. 389,337, me@

Il. i5 

